The invention relates to apparatus and a method for bending coiled tubing.
It is known from WO 2011/071389 to provide an injection module for lateral insertion and bending of a coiled tubing via a side opening in a well. The module comprises an insertion device for insertion in a side opening in a well, for example a petroleum well, an injection well, a water well or a geothermal well. The insertion device has a bending head which defines a bending path along which a coiled tubing is fed laterally through the side opening. The bending path is curved so as directionally to deviate the coiled tubing as it is fed along the path. The coiled tubing may thus be deviated from a lateral direction to a downward direction, for example into an annulus between casings in the well. The bending head is designed to deviate the coiled tubing through approximately 90°.
Downstream, in the direction of insertion, of the curved part of the bending path where the coiled tubing has been bent, it is desirable to stabilise or straighten the coiled tubing from the bent condition to a generally straight condition. In one embodiment, in which the bending path is provided by a curved passage, this is achieved by providing a straight downwardly directed passage downstream of the curved passage. In another embodiment, in which the coiled tubing is passed between two opposed rotating wheels, one of which forms the inside of the curved bending path, a directional stabiliser is provided downstream of the opposed wheels. The directional stabiliser has a concave contact surface for engaging laterally against the coiled tubing so as to steer it directionally as it is discharged from the bending head. The supporting force exerted by the directional stabiliser on the coiled tubing is adjustable by means of a hydraulic piston.
In both embodiments, both the bending part of the insertion device and the straightening part are sized to fit within the diameter of the side opening of the wall of the well. The straightener, which is at the outlet of the insertion device, can therefore be inserted into the side opening and adopt a position radially inwardly of the wall, e.g. inside the annulus between casings, where the straightening process is carried out.